Theory:
A charged battery has it atoms lined up all in a row, polarized so to speak, with electrons at one end and protons at the other. My thought is that this somehow stabilizes the atomic structure internally. When the battery is dropped it is stable.
A discharged battery does not have it atoms lined up all in a row, they are not held in place and are scattered as far as polarity is concerned. This seems to provide internal instability and a wobbly battery when dropped.
Then there is the little dimple on the bottom of the battery that you can't see, one has been tampered with... :stirpot:
My two atoms worth